Daniel and Kelly’s Extraordinary Universe - Where Does The Earth's Magnetic Field Come From?

Episode Date: February 19, 2019

What causes our planet to generate a magnetic field? What is a magnetic field?!? Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

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Like a force field? Yeah, basically, it protects us from cosmic radio. and space weather and all sorts of crazy radiation. That's amazing. That's like Star Wars, right? Like all the spaceships have a force field that protects it? How do we have this field? It's pretty amazing.

It's the Earth's magnetic field, actually. What? Is that suddenly less exciting to use it less magnetic than a force field? It's not very attractive, unfortunately. No, I mean, what do you mean? It's just like the North Pole and the South Pole. Is that what you mean? Yeah, the Earth's magnetic field serves a really important purpose, but what a lot of people don't know about it is that it's changing. It might not be around forever.

Oh, what? I'm Horan. And welcome to our podcast, Daniel and Jorge, explain the universe. In which we take everything about the universe and try to make sure it makes sense to you, things in the sky and things under our feet. That's right. All the positive things, all the negative things in the universe. All the north things and all the south things. That's right. Today on the program, we're going to ask the question, what's the source of the Earth's magnetic field?

Like, why is the Earth a huge cosmic magnet, right? Like, that's crazy to think about. Like, that's basically what we are. We're just a giant flying fridge magnet. That's right. And the Earth is a huge magnet. It's really powerful. And this huge single magnetic field envelops the entire Earth.

It protects us from radiation, allows us to navigate. Like, where does it come from? Why does it exist? Are we lucky to have one? Does every planet have one? Where does it come from? Can we turn it off? I have so many questions.

And it's super important because without the Earth's magnetic field, we would literally be toast, right? Like we would just get burned to crisp. Is that a technically accurate use of the word literal? Like, would you turn into toast? Like, could I spread butter on you and eat you for breakfast? You know, depends on what you like. I'm not sure I'm into toasted Jorge for breakfast.

Toasty. But, yeah, without the magnetic field, there would be a huge amount of radiation that just bombards us. As we said before, the magnetic field bends the path of charged particles. It deflects them. So it doesn't like stop them. It's not like a force field where it goes and it gets fizzled out

or anything. It just bends them. But if a charged particle is moving really fast, then all you need to do is deflect it and it'll go somewhere else instead of right into your brain and give you cancer. Right. And it's not just like a little bit of charged particles or it's a lot. Like the field is doing a lot

right now. Yeah. It does a lot of Without it, we wouldn't have an atmosphere, right? We wouldn't be able to breathe. Really, the earth wouldn't be the same. Yeah, it does a lot of heavy lifting every day. Most people just ignore it, you know? Most people aren't even aware of everything that's being done for them by the magnetic field. You ever wonder if it feels resentful, if it's like, man, nobody ever gives me props.

I'm doing all this work here. Everybody just takes me for granted, right? It should just turn itself off for a few days just to teach us a lesson. Yeah. I think people do take it for granted. It's kind of like nobody ever pays attention to which way is north. You just think that it's always going to point to the same direction. But it's not, right? Exactly. And we've had a magnetic field for billions of years.

As far as we know, the Earth's magnetic field formed pretty soon after the planet came to be. Okay, yeah, that's something I didn't know. And in fact, let's talk about a couple of things that maybe people don't know about the magnetic field. Some interesting facts about the magnetic field is that it's not perfectly aligned with our rotational axis. That's pretty surprising to me. Yeah. It's off by about 11 degrees, right? Yeah, the Earth, it's like it has two North Poles, right?

What? One is the one it spins around, right? The whole Earth is spinning, right? So it gives us day and night as the Earth turns towards and away from the sun. Yeah, we're spinning. The Earth is spinning, and so if you put a line through, around, where it's spinning, you would get one north pole, but you're saying

the magnetic north pole is not aligned with that one. That's right. It's not exactly aligned with it. So if you were standing on the rotational north pole, the point around which the earth is spinning, right, and you looked at a compass, it would point away from that place.

It would say, nope, you're not at the magnetic north pole. Oh, wow. Because the, wait, so then where does Santa Claus live? Does he live in the rotational north pole or the magnetic north pole? Or does he have two houses? That's a big secret. I think we should save that for an entire other podcast.

So the magnetic north pole is different from the rotational north pole. Wow. They're different by 11 degrees. I remember it's like 360 degrees all the way around the circle, 11 degrees. So it's not a big difference. If you're in the U.S. or in South America or whatever or in Asia, you can mostly use a compass. It's going to point pretty close to the top of the earth as we think about it rotationally. Right.

But not exactly. Wow. It's a big deal if you're in the North Pole, right? I mean, 11 degrees must be like 1,000 miles or something. Yeah, as you get closer and closer to the North Pole, it becomes a bigger and bigger deal, right? So that if you're standing on with the line that Earth rotates around, it's going to be kind of a big deal that the North Pole is far from there. But if you're far away from it, like most people are, most of our listeners are,

then it's not really an issue. But I think it raises the interesting question. Like, why aren't they aligned? Where does the magnetic field come from, right? Like, is it a big bar magnet inside the earth that got like knocked over and tilted? Is it something totally different? That's why I think it's quite fascinating. So it's 3.4 billion years old, meaning that before 3.4 billion years, we didn't have a magnetic field.

Yeah, that's right. And it's basically because earlier than that, the Earth was just a hot ball of nasty magma and nothing was really organized. And so before that, we didn't really have all the structures we needed to generate the magnetic field. And so it was just like a, yeah, it was just a ball of lava in space, basically. Oh, a giant lava lamp. Yeah, exactly. A hot drop of rock. We've gone from fridge magnet to lava lamp.

I guess we'll get more into how that works. But this is an interesting semantic point, which is that the North Pole, but we call the North Pole, is actually the magnetic south pole. Yeah, it's one of these things about definitions, right? It's like when they discovered electricity, You know, they defined positive negative currents, and it turns out then electrons have negative charge, right? It's just a definitional thing.

But when they first figured all this out, they defined north as, you know, whichever side of the magnet points towards the Earth's north pole. But that actually makes it the south, right? Because the south pole of a magnet will point towards a north pole of another magnet, right? And so that's just a definitional thing, but it's kind of funny. Yeah.

So if you're holding onto your compass, the magnetic north pole of your compass points, of course, towards the Earth's North Pole. That means Earth's North Pole is magnetically south, right? Because the north pole of your compass is attracted to it. So we should change the name or change the laws of physics. Which one should we do first? Let's come up with better names, right? Like not north and south, but like apples and oranges.

I live four blocks apple of here. Is that the general idea? I always thought it was weird that it was north and south. I mean, I understand where it comes from. It comes from the geographical question, where are we and the earth rotating and stuff. But from a physics point of view, we like to think of these things as like positive and negative, right? All the other charges we think about, like electric charge and gravitational charge or weak force charge. We all think about those in terms of positive negative numbers.

So north and south is sort of archaic. So if I had to redo it all over again, I would just define one of them as positive and one of them is negative, right? There was like a big magnetic battery. And then we wouldn't be so concerned about the North Pole not being aligned with the rotational North Pole. Yeah, we would probably have a big political question? Like, would you rather have the North Pole be positive or negative, right? Everybody probably wants to be positive. And the Southern Hemisphere would argue, we should be positive.

You guys are so negative up there. You're being colonial. Exactly. That's right. That's right. Okay, so those are some pretty cool facts about the Earth's magnetic. field. But now let's talk about what's the source of it? How come we have a magnetic field and other planets don't? And I think a really important clue there is the fact that the magnetic

field is not static. It's not just like, here's the magnetic field, it's always been this way, it's always going to be this way. A big clue that the source of the Earth's magnetic field is something weird and interesting is that the magnetic field is changing. You know that the magnetic field is moving. It's moving quite a bit. And it's also getting weaker, like the magnetic field was much, much stronger when the Romans were in charge of the world than it is today. Really? And, yeah. Even just a thousand years ago, a couple thousand years ago.

Absolutely. Wow. And eventually, it might even flip, right? It might be that positive becomes negative. North becomes south. Wow. And so that's quite interesting, right? It tells us that there's something really interesting going on making that magnetic field. So let's dig into that.

Yeah, let's talk about that. But we were wondering how many people out there knew or had this idea that the magnetic field is not something that's a given on Earth. How many people out there knew, what's the source of the Earth's magnetic field? Yeah, so I went around and I asked a bunch of unsuspecting undergrad that you see Irvine and said, what do you think about this question? So before you hear their answers, think to yourself, do you know where the Earth's magnetic field comes from?

Could you explain it? If you had to build a planet from scratch, how would you make sure it had a magnetic field? Yeah. Would you put just a bunch of fridge magnets in the middle? Like a bunch of fridge magnets. Well, here's what people had to say. Something to do with the core. The crust. Gravity?

The atmosphere, I'll know. Okay. Gravity? Um, I assume it's the rotation of the Earth's core. Is it the core? The core. The poles north and south pole. Okay.

All right. I think this is a pretty good credit to those students at the University of California at Irvine. Pretty good consistent answers. You mean the ones that said gravity? It's always gravity. Come on. Turns out actually they're not entirely wrong. Gravity, as always, plays a role. My favorite answer was the one that said the North Pole and the South Pole. That gives the magnetic field.

It's like, cool, cool, good complete answer without actually revealing any information. Yeah. And not making fun of these people, of course. You know, I put them on the spot, answer a random physics question. I'm just impressed that they're even willing to share their thoughts with me. Yeah, no, it takes a certain amount of bravery to talk to you in public, Daniel. I don't even know how to respond to that one. No, I usually try to avoid talking to myself in public also for that same reason.

Yeah, it's not, it's frowned upon. But no, what I mean is a lot of people answer They knew it had something to do with the earth's core Something about the core and the magma and the crust Something about the something going on inside the earth itself Yeah, yeah And it's like thinking about the earth is a big machine, right? Which is kind of crazy

Because you walk along the surface of the earth And you think of it just as a big rock, right? But underneath there are powerful forces And crazy things happening And all that is happening in order so that you can have a magnetic field. So I'm just glad that people are aware of all the work the Earth is doing for us.

Yeah, there's stuff happening inside the Earth, right? Like it's an active machine. It's an active device. Yeah, absolutely. It's like a boiling kettle of magma and crazy stuff is happening in there. And if it wasn't, we wouldn't have a magnetic field. So we're glad to have sort of a young, hot planet.

Yeah. Well, let's get into it. But first, let's take a quick break. A foot washed up a shoe with some bones in it. They had no idea who it was. Most everything was burned up pretty good from the fire that not a whole lot was salvageable. These are the coldest of cold cases, but everything is about to change. Every case that is a cold case that has DNA.

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I'm an engineer, and I have to admit that I don't really understand how magnets work. So I thought maybe we should... Well, welcome to the podcast. You came to the right place. This sounds like a great episode. I'll tune in. But let's take a step back maybe and talk about just magnets in general. Yeah, magnets are really pretty amazing.

one of my favorite things because they're like physics that you can see with a naked eye, right? You can see a fridge magnet sticking to the wall. You can even get these things to push away from each other without touching. It's like the first sign of a force that you can really play

with and identify with. It almost looks like magic. Of course it's not because we understand it. But it has something in common with it, right? It's powerful. It's visceral. It's physical. It's right there in front of you. It's a lot of fun. Because most things don't act like magnets, right? Like most things don't stick to the wall if you put them there.

Most things don't push against you without any direct line of connection, right? It's weird. I don't know. How many things have you tried? I've thrown a lot of different things at the wall and a good number of them actually stick. You know, spaghetti sticks to the wall, eggs sticks to the wall, lasagna sticks to the wall, lots of different kinds of foods. Don't you have young kids? You should be aware of how many things do actually stick to the wall.

Once again, I'll decline your invitation to visit your house. just wear, you know, all rubber clothing. It's no big deal. I mean, we just hose off after dinner. No, you're right. And not everything is a magnet, right? And so not everything sticks to things. And so let's talk about that a little bit.

How do you, how does something become a magnet? What makes something a magnet and something else not a magnet, right? The amazing thing is that it's all about electrons. Okay. Like the kind of magnet that you're familiar with, you know, a fridge magnet, a normal, like a piece of metal that's become magnetized that sticks to something. How does that work? well, the way that it becomes a magnet

is because it has billions of tiny little magnets inside of it. Each electron has something we call quantum spin. And it's not actually spinning around or doing anything physical. It's a quantum mechanical property. We call it spin, and it generates

a little magnetic field. So this electron does this weird thing, and it generates a very tiny magnet. So every electron is like a little magnet. So it's not actually spinning. physicists have just are spinning it as if it was spinning. That's right.

It's physics spin. Yeah, we use the word spin because the thing it does, the quantum spin, has a lot of similarity with physical spin. Like the mathematics we used to describe physical spin, angular momentum,

a lot of that mathematics can be copied over and applied directly to quantum spin. And that's what makes it compelling as a concept. And we should have a whole episode about what is quantum spin because it's fascinating.

But the point is that each electron itself is like a magnet. It's like a really tiny little magnet with a field. Yeah, it has its own little magnetic field. And in some kinds of materials, the way the electrons are organized in their shells, et cetera, gives you an overall magnetic field for the atom. And in some of them, they don't. They just cancel out.

You get nothing. Right. And some of them, you do get little magnets for the atom. And then in some of those atoms, they like to organize in a way. so all the magnetic fields are aligned. So, for example, in iron, and a lot of metals have these properties that you can align all the little magnetic fields of the atoms, so they point in the same way. So when you have a piece of magnet, like a chunk of metal that sticks to your fridge, the reason it has a magnetic field is because all those tiny little magnetic fields are all going in the same direction, so they add up to kind of a big magnetic field. You have another piece of metal that's not magnetized, and they're just sort of scrambled.

They're all in different directions. So there are magnetic fields in there, but they're all just sort of canceling each other out. Right. And it's not just metals. I mean, like you and I and the cheramon, this wooden cheramon, it also has these billions of tiny little magnets. But the problem is they're not all pointing in the same direction, so they all cancel out. And so overall, it's not a magnetic thing. Yeah, exactly.

Yeah, to be magnetic, you need to have these little magnetic fields, and you have to have a structure where the substance likes to organize in a way, so they all point in the same direction. So we're all magnetic. we all have magnetic personalities you want me to tell you you're a magnetic dude you're a magnetic dude that's funny and that's how something can become a magnet also right like you have a normal piece of metal and it sits next to a magnet

for a long time right how does that become a magnet well the first magnet is aligning all the little magnets in the other one it's pushing them in the same direction so eventually becomes a magnet itself right but let's let's see if we can get into it maybe a little bit more. So what does it mean that each electron is like a little magnet? Why is that? Why does

the electron have a field? You know, like why isn't it a pointed field? Well, there's a very close connection between electricity and magnetism, right? In fact, we think of them as one theory, electromagnetism. And there's a lot of connections. Like, anytime you get electricity moving in a circle, that makes a magnetic field. Okay. And the other, it works in the other direction too. Any magnetic field that changes in time will generate electric currents. So we think of these things,

electricity and magnetism is sort of separate. Turns out they're really closely connected. They're really just two sides of the same coin. And that's why it's not really surprising that the electron, which is like the most basic charged particle we have, could generate electric fields. Because in the end, it's a charge

and it's not physically spinning, but it has quantum spin. And so you can think of it as like having a small quantum magnetic field. It really is a quantum mechanical effect. Like every fridge magnet is a quantum mechanical effect. Wow. So it's just something kind of embedded

in the laws of the universe. It's that whenever you have something with charge, like an electron, is just sort of automatically by the laws of physics associated with a magnetic field. Yeah. Charges plus motion gives you magnetic fields. In this case, the motion is the quantum

spin. Right. And that's how you can make a non-permanent magnet, right? Like, that's how you make electromagnets. Exactly. So there's a little electrons, they spin and they make their own little magnetic field. But you could also do something else with them is that you can move them in a circle, right? Make a loop of wire and

pass electricity through it, and it generates a magnetic field. Why? Well, that's just one of the Maxwell's equations. That's one of the laws of electricity and magnetism. That currents moving in a circle will generate a magnetic field because magnetic fields and currents

are very closely connected. As I said before, There's just really two parts of the same thing. This is pervasive quantum field that fills the universe, right? That lets us tap into the electromagnetism at any point. And moving charges through it will generate the magnetic field. Right. So it's kind of like if you take a bunch of electrons and you get them to go in a move in a circle, they all sort of align and add up to create all of their little magnetic fields

out up to create a big magnetic field in the center of the circle. No, it's not their personal magnetism. fields, like the ones that come from their quantum spin, it's the fact that they're moving in a circle generates the magnetic field in the center. So they still have their own little fields from their quantum spin, but it's their motion in a circle. The current moving in a circle will generate magnetic field as well. Wow. But why? Hmm. It's a deep question, man. I think there's a technical way to think about that question, which is look at the equations to describe it. And those equations have symmetry in them. They're called Maxwell's equations. You can Google them and look at them.

And they show you that electric fields and magnetic fields really are connected. But I think the intuitive way to think about it is just as part of one, right? It don't think that moving currents generates magnetic fields like this one kind of thing generates this other kind of thing. Just think of them as part of one combined thing, right? There's a close connection between, electric fields and magnetic fields. And a fascinating insight comes from thinking about how electric and magnetic fields change if you look at them from different

velocities. Like if you have an electron at rest, it mostly gives you an electric field, right? It's a very small magnetic field because of its quantum spin. Let's ignore that for now. But somebody else driving by, they see that electron not at rest. They see it as moving, right? And moving charges give magnetic

fields. So if you're at rest with respect to the electron, you mostly see it in electric field. If you're at motion with respect to the electron, you see an electric field and a magnetic field. This really is a clue that the two are different parts of the same thing. And you see different parts of it if you're

moving at different speeds. So they really can't be separated. They're really just two parts of the same beast. Oh, I see. Okay, so that's magnets. They can either be permanent, meaning that it's just the electrons inside of the material adding up

to make a big magnetic field. Or you can also make it a field by moving electrons around in a circle. Okay, so the Earth is which of the two? Is the Earth a permanent magnet or is it like an electric motor? Well, it's a great question. For a while we didn't know because it could have been that the Earth had basically a bunch of permanent magnets buried in it, right? Because, you know, there is this crust and it's got a lot of rock and a lot of those rocks are metallic. And you might imagine maybe there's just a bunch of magnets and they all got a line somehow, right?

Yeah, that wouldn't make sense, right? It would make some sense, right? You can imagine that happening, and the sun has a big magnetic field, so you can imagine maybe the sun magnetize the earth. Well, before we go too far into that crazy speculation, the answer is no. The earth is not a permanent magnet. And we know that because the Earth's magnetic field seems to penetrate from the core, right, not from the crust, and also because it's changing.

It's not static. It's not the same all the time. And a permanent magnet, by definition, it would be permanent, right? If it came from a bunch of buried magnets inside the earth, then those wouldn't be changing. But in fact, we do see the Earth's magnetic field changing. So how fast is it changing? Is it changing by the hour or by the 1,000 years?

It's more on the thousands of years schedule, but we don't really know. The amazing thing is that we can see the history of the Earth's magnetic field. And the way we can do that is that we look at magnets being generated over time on the sea floor. So there's these like volcanoes that spit up magma and lava and stuff on the surface. the floor of the ocean. What happens when they come at the floor of the ocean is of course they cool very quickly because, you know, all that cold water and lava and it cools very quickly.

But the lava is sometimes magnetic, right? It has a bunch of little magnets in it. And so what happens before they cool is they get aligned with the Earth's magnetic field and then they get frozen. So each of those rocks is like a picture of the strength and the direction

of the magnetic field when it was formed. Wow. I was about to ask you how we know. Have we been measuring the magnetic field in our history books, but we don't have to. It's kind of embedded in the earth itself, the history of its field. Yeah, it's really amazing. And because the volcanoes underwater just continuously spew this stuff out, we have this like unbroken record of the strength and the direction of the earth's magnetic field over thousands and thousands and millions of years. Wow. And that's the crazy thing is that not only is the earth magnetic field

changing like it's getting weaker and it's sliding off the North Pole a little bit it used to point the other way what? Yeah like 180 degrees yeah exactly like if you jumped into a time machine with a compass today and went back 800,000 years

the compass would point in the other direction okay so there's stuff going on and it's changing which means that the earth is not a permanent magnet we're not a giant fridge magnet floating through space so what's going on in there what's what's causing the then inside the earth?

Yeah, well, it's kind of a mess. But, you know, the one option is permanent magnets. If it's not that it has to be a current, right? You need some sort of charges moving in a circle to generate a magnetic field. So what could be doing that? It's not like somebody built a huge machine made of wires down under the ground, right? Instead, what we have, sort of a basic picture of what's inside the Earth is you have the crust, which we're standing on.

Under that there's a big liquid layer of, you know, various rocks and metals. And then there's a solid core, right? core right and that liquid layer is sloshing around there's a lot of heat that's coming up from the gravitational pressure and from the radiation of all the crazy stuff inside the earth it's keeping that sort of bubbling and frothing it's like a big soup of liquid metal and basically the currents in that soup of liquid metal are what's generating the magnetic field so all those electrons in that soup moving around in a circle is what creates the earth magnetic field yeah if you take something that can conduct the electricity like iron

and you melt it down, right? And you slosh it around in a circle. You'll be generating little magnetic fields because you have electrons and they're moving in a circle, right? And it's a little bit more complicated than that because it's not like the liquid inside the earth is just slowly moving in a circle and that generates

the magnetic field. It's much more turbulent than that, right? This convection going on is things that are dense fall and things that are light bubble up to the top and that's making all this swirling. And there's this cool effect called a dynamo. And what happens is you get a little magnetic field

from some initial swirling. And because electricity and magnetism are so closely connected, that magnetic field will push electrons around. Like we said, the magnetic field of the earth deflects charged particles, right? Well, when you get a magnetic field started in the earth, it builds on

itself because the motion of the electrons gives you a magnetic field. That magnetic field pushes those electrons around even more, which gives you more magnetic field. So it's sort of a feedback effect. Oh, like a perpetual motion machine, kind of. It's like feedback.

Yeah. The source of energy is that you have this, all this heat that's coming from the gravitational pressure, the earth being squeezed by its own stuff, and the radiation. So it's not like a perpetual motion machine because it's constantly being fed energy, right? So it's more like a bubbling cauldron of stuff, right, that generates these magnetic fields. And its motion is sort of related to the Earth's rotation, right? I mean, it's like the earth spinning is kind of what creates these currents going in a certain direction, which is why the magnetic field is sort of aligned with this rotational axis of the earth.

Yeah, exactly. These currents are the earth moving relative to its liquid core, right? If you ever held like a ball that has liquid inside of it, you know, they don't roll normally, right? If you have a ball half filled with liquid, you roll across your garage floor, it's going to go all one. and be really unpredictable, right? And if you spin it, similar things happen. So it creates crazy currents inside of it. And so this is like, it's hot and it's bubbling and it's spinning.

So you definitely get lots of really complex fluid dynamics going on inside there. But it's related to the spinning, but it's not completely dependent on the spinning, which is why the two axes are not aligned. That's right, yeah. But they're definitely related, right? Yeah. But what's generating the magnetic field, the short version is that it's, you know, spinning hot liquids inside the earth.

Spinning magnetic conducting liquids inside the earth are generating our magnetic field, which is crazy, right? Yeah, the earth is hot, it's magnetic, it's attractive. It's amazing to me that it's stable at all, you know, that that would like not just be pointing in all sorts of random directions, you know, like you watch a pot of water bubble, right? And it's crazy. It's going crazy all the time. It's this direction, in that direction. Then somehow the Earth's magnetic field is surprisingly stable, given all the craziness. that's happening under our feet.

Well, let's talk about that. But first, let's take a quick break. A foot washed up a shoe with some bones in it. They had no idea who it was. Most everything was burned up pretty good from the fire that not a whole lot was salvageable. These are the coldest of cold cases, but everything is about to change.

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I'm Dr. Joy Hardin-Bradford, and in session 421 of therapy for black girls, I sit down with Dr. Ophia and Billy Shaka to explore how our hair connects to our identity, mental health, and the ways we heal. Because I think hair is a complex language system, right, in terms of it can tell how old you are, your marital status, where you're from. you're a spiritual belief. But I think with social media, there's like a hyper fixation

and observation of our hair, right, that this is sometimes the first thing someone sees when we make a post or a reel is how our hair is styled. You talk about the important role hairstylists play in our community, the pressure to always look put together,

and how breaking up with perfection can actually free us. Plus, if you're someone who gets anxious about flying, don't miss session 418 with Dr. Angela Nealborne. where we dive into managing flight anxiety. Listen to therapy for black girls on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast.

I'm Dr. Scott Barry Kaufman, host of the Psychology Podcast. Here's a clip from an upcoming conversation about exploring human potential. I was going to schools to try to teach kids these skills, and I get eye rolling from teachers or I get students who would be like, it's easier to punch someone in the face. When you think about emotion regulation, like you're not going to be. going to choose an adaptive strategy which is more effortful to use unless you think there's a good outcome as a result of it if it's going to be beneficial to you because it's easy to say like go you

go blank yourself right it's easy it's easy to just drink the extra beer it's easy to ignore to suppress seeing a colleague who's bothering you and just like walk the other way avoidance is easier ignoring is easier denial is easier drinking is easier yelling screaming is easy complex problem solving You know, takes effort. Listen to the psychology podcast on the IHartRadio app, Apple Podcasts, or wherever you get your podcasts. Let's get into that. Is it stable? You said earlier that it flipped a long time ago and it's moving over thousands of years.

That doesn't seem super stable. Our magnetic field is remarkably stable compared to others. like the magnetic field of the sun, it flips direction every 11 years, very regularly. What? Yeah. The sun's magnetic field, like, has a huge impact on the solar system. Like, where do charge particles go?

And how does the solar wind blow and all this kind of stuff? And every 11 years, it just flips. Flips. So what causes it to flip? I mean, on Earth, what causes our field to flip? We don't really understand it, but the short version is that it's a big hot mess and it's sort of unstable. And so, you know, it's mostly supporting itself and you get a feedback effect, but these things can be crazy.

It's like when you roll that half-filled ball across your garage floor, sometimes it mostly roll straight. Sometimes it has a crazy loop. And so if one little random thing happens, it can push it sort of off course that can build on itself and feedback in the wrong direction. So these are instabilities from equilibrium. And once that happens, it can very quickly go off course. imagine you're like driving your car down the freeway at 90 miles an hour you know everything's going fine and you're and it's all good suddenly a tire pops right and you're flipping over

or you veer you know your kid makes a noise in the back seat and you pull your hand on the steering wheel a little bit you start going in the wrong direction it's suddenly very hard to get back on track driving smoothly right it's sort of like that with the magnetic field one little random effect one little random occurrence can sort of build on itself and make things go crazy and eventually things can even flip over and go the other direction.

It's kind of like a chaotic system. Absolutely. Absolutely. That's the word. It's a chaotic system. So what happens when it flips? Does it just happen overnight? Like one day I'll see my compass pointed one way and then suddenly I'll see it pointed the other way or does it build over hundreds of years? Well, the fossil record we have is not very precise down to like the minute or the year or something. But as far as we can tell, it doesn't happen overnight. You know, these things are all geological timescales.

So it takes a little while. But the interesting thing about the Earth's magnetic field is that the periods of flipping are not predictable as far as we can tell. Like, sometimes it'll flip like, you know, every 100,000 years it'll flip. Sometimes it'll go 50 million years without flipping. But does it flip 180 degrees or can it flip sideways? It flips usually so that the North Pole is at your household. I want to be Santa Claus. I've always thought you

kind of look like Santa Claus I'm the Chinese Panamanian version of Santa Claus Santa Claus Many people don't know that's the actual historical origin Yeah of Santa Claus Like everything else

We've just stolen our culture No it's There are two more stable situations And one is You know the North Pole On the Earth's rotational North Pole And there's one is on the Earth

Rotational South Pole Oh I see Those are the stable configuration, because they sort of align with the spinning of the earth. Exactly. It can't just be random because the spinning of the earth does play a role in generating those currents and maintaining them. Oh, I see. But maybe there's a few thousand years in between where it's sort of wandering around the earth. Yeah, exactly.

And it can drift. And that's what's actually happening right now. Like right now, the Earth's magnetic pole is moving 40 kilometers per year. 40 kilometers. Wow. That's a lot. I was stunned. It's fast, right?

I mean, you might think, well, 40 kilometers per year is not a lot of meters per second, and that's true. But, you know, that adds up over a bunch of years. And not only that, but it's getting weaker, right? It's getting weaker every year by several percent. We don't know what's going to happen because we can't predict these things. But, you know, if you do sort of like a trivial straight line trajectory, then it's getting weaker and weaker, and it might eventually flip. You know, we have records from earlier times when humanity was around, and like the Romans

they had a magnetic field that was twice as strong as ours is. Wow. So it's definitely active. It's not like it's right now just hanging out. Like things are happening. The magnetic field in a thousand years could be different dramatically than it is today. Oh. So if I took just like a regular compass and I set it on my table and I filmed it for, you know, a couple of years

and then I sped up the video fast forward, I would sort of see it. You might see it drift a little bit. Yeah. Yeah. If you wait long enough and you're far enough north, then yeah, you could see the compass drift a little bit exactly and you know i wonder about things like animals you know a lot of animals use the magnetic field for navigation right we've recently figured out that like birds some of them can see magnetic fields and use them to help figure out where to go i wonder if that like totally

screws up the birds yeah well 40 kilometers a year it's it's a lot i mean that means Santa Claus every year has to move 40 kilometers has to pack everything up the whole factory you know moving sucks oh it's such a drag man you've got all that stuff in the workshop At least he's got a little elves to help him, right? Yeah, maybe that's why he has elves, you know, just to help him move. Originally, that's why he contracted the elves. But, I mean, it's not a little bit. It's 40 kilometers.

Every year you have to pick up, move 40 kilometers, and that's where the new North Pole would be. The magnetic North Pole, yeah, exactly. Yeah. Okay, and you said it's getting weaker. Yeah, exactly. It's getting weaker also. It's like just not as strong. A thousand years ago, it was stronger than it is today, and every year it's getting a little weaker.

And we don't know what's going to happen next year. It might drift back towards the rotational North Pole and get stronger, right? These things are unpredictable. But there are a bunch of people working on this, and they have really complex computer simulations that describe all the physics we think is happening inside the earth. And until recently, those simulations didn't agree with what we were seeing. But now they're more sophisticated, and they can model all the complexities. And the simulations are pretty good.

So we think we have some understanding of all the crazy effects that are happening in there. And they even do predict things like the Earth magnetic field flipping. They can't specifically predict when our magnetic field is going to flip. But, you know, they have a computer model in which sometimes they see it flip. Right. But this idea that it's protecting us and keeping our atmosphere in place, we don't need to worry about that, right? Like it's getting weaker, but it's not going away. Should we worry?

That's sort of a deeper philosophical question, you know? In general. In general, should we worry, my Jewish grandmother says yes. I think we're not likely to lose our magnetic field, right? Look at a planet like Mars, right? Mars used to have magnetic field, but it doesn't anymore. And the reason is that its insides have gone quiet, right? It's cooled and it no longer has, like, a lot of crazy stuff happening on its inside,

so it lost its magnetic field. That's not likely to happen to the Earth anytime soon. And so we're going to have some sort of magnetic field. protecting us from space. It may be stronger, maybe weaker, may you point in another direction, but we're likely to still keep this force field. Okay, so I don't need to stockpile on sunblock or sunshades. Refrigerator magnets.

Yeah, solar panels. I wonder how many refrigerator magnets it would take to protect yourself from cosmic rays. All those tinfall hat people, little do they know, it's fridge magnets. You've got to put them on your head. We're going to spawn a whole generation of refrigerator. magnet hat people now. Yeah. We should sell those in our store.

Oh my gosh. Let's sell refrigerator magnet hats in our store. Force field hat. Personal force field hat. There you go. And actually would be real science. It really does generate a force field and it really does deflect radiation.

Yeah. Oh my gosh. Somebody get the lawyers on that. Yeah. We need to open danielanhorpe.com slash store, ASAP. Slash crazy science protection story. All right, well, let's take a step back here. I mean, it's pretty amazing to think that our planet is currently in our solar system.

It's special because we have this magnetic field. And without it, there wouldn't really be any life on it. That's right. But, you know, a lot of planets have magnetic fields. Jupiter has one. all the big gas giants have one basically any planet that's rotating and has stuff going on inside it has a magnetic

field so we expect that a lot of rocky planets out there probably have magnetic fields but like Mars doesn't have one absolutely essential yeah Mars is sort of unusual right Mars and Venus also doesn't have one right yeah that's what I mean and we have a it helps us have an atmosphere

and life and so we really wouldn't be here without the Earth's magnetic field no props to the magnetic field man it's absolutely essential yeah And without it, it would blow away our atmosphere, right? The solar wind wouldn't be deflected. It would rob us of atmosphere slowly over time, like what happened to Mars. So it's definitely very important.

Yeah. And, you know, we still have a lot to learn about sort of extra planetary magnetic fields. Like, I would love to understand why the sun's magnetic field flips so regularly and so dramatically every 11 years. It's a mystery. And, you know, we even have moons out there in the solar system with magnetic fields. Our moon doesn't seem to have one because it's basically a lump of rock. it might have happened earlier in its lifetime but Ganymede

is big enough to have like stuff going on inside it to have its own magnetic field so it's sort of like a property of a planet when it gets like big enough you know it's like when you're a real planet you have a magnetic field yeah it's amazing to think that at the scale the solar system things are kind of chaotic

right the solar system is changing all the time it's doing crazy stuff it's flipping its fields yeah the earth is not just a rock right it's like a really big machine doing crazy stuff out there in space for us. All right. I hope we found that an attractive topic

with two magnetic personalities. Current importance. I hope that charged you up for your day. Yeah. And maybe the next time you go out there and you think about the fact that you are swimming in this amazing and

unpredictable field that is protecting the earth. Yeah. So go out there and get the feels for your magnetic field. Thanks for joining us. See you next time. If you still have a question after listening to all these explanations, please drop us a line. We'd love to hear from you. You can find us at Facebook, Twitter, and Instagram at Daniel and Jorge. That's one word. Or email us at Feedback at Danielandhorpe.com.

Get fired up, y'all. Season two of Good Game with Sarah Spain is underway. We just welcomed one of my favorite people, an incomparable soccer icon, Megan Rapino, to the show. And we had a blast. Take a listen. Sue and I were, like, riding the lime bikes the other day. And we're like, we're like, people ride bikes because it's fun. We got more incredible guests like Megan in store, plus news of the day and more.

So make sure you listen to Good Game with Sarah Spain on the IHeartRadio app, Apple Podcasts, or wherever you get your podcasts. Brought to you by Novartis, founding partner of IHeart Women's Sports Network. Don't let biased algorithms or degree screens or exclusive professional networks or stereotypes. Don't let anything keep you from discovering the half of the workforce who are stars. Workers skilled through alternative routes rather than a bachelor's. degree. It's time to tear the paper ceiling and see the stars beyond it. Find out how you can make stars part of your talent strategy at tear the paper sealing.org. Brought to you by opportunity at work

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